Mostly because when I see an em dash now, I assume that it was written by AI, not that the author is one of the people who puts enough effort into their product that they intentionally use specific sized dashes.

AI might suck, but if the author doesn't change, they get categorized as a lazy AI user, unless the rest of their writing is so spectacular that it's obvious an AI didn't write it.

My personal situation is fine though. AI writing usually has better sentence structure, so it's pretty easy (to me at least) to distinguish my own writing from AI because I have run-on sentences and too many commas. Nobody will ever confuse me with a lazy AI user, I'm just plain bad at writing.

To continue the story, the guy saying this got fired and probably wouldn't have without taking this stand.